In U.S. Pat. No. 4,219,559 there are described a number of 1-substituted N-heterocyclyl-4-piperidinamines as compounds having useful anti-histaminic properties. The same reference also teaches the use of a number of N-heterocyclyl-4-piperidinamines having a piperidine moiety which is either unsubstituted in the 1-position or substituted with an alkyloxycarbonyl or phenylmethoxycarbonyl group, as useful intermediates. A number of these compounds are further described in more detail in J. Med. Chem. 1985, 28, pp. 1925-1933, 1934-1943 and 1943-1947. Furthermore, in J. Med. Chem. 1985, 28, 1934-1943 there are described the synthesis and anti-histaminic properties of the compound 1-[(4-fluorophenyl)methyl]-4-(4-piperidinyl)-1H-benzimidazol-2-amine dihydrobromide. The latter compound is taught in "Astemizole: a New, Non-sedative, Long-acting H.sub.1 -antagonist, Med. Publ. Found. Symp. Ser. 84, 25-34 (1984)" to be an active metabolite of astemizole.
In U.S. Pat. No. 4,556,660 and in the Published Eur. Pat. Appl. Nos. 145 037, 144 101 and 151 824 there are described further series of N-heterocyclyl-4-piperidinamines having a 1-substituted piperidine moiety as compounds having useful anti-histaminic and serotonin-antagonistic properties, while N-heterocyclic-4-piperidinamines being unsubstituted in the 1-position of the piperidine moiety are described as intermediates.
Finally, in the published Eur. Pat. Appl. No. 151,826 there are described a number of 4-(bicyclic heterocyclyl)methyl and -heteropiperidines having useful anti-histaminic and serotonin-antagonistic properties.
The present invention concerns compositions containing the previously-mentioned N-heterocyclyl-4-piperidinamines bearing either a hydrogen atom, an alkyloxycarbonyl or phenylmethoxycarbonyl group in the 1-position of the piperidine moiety as active ingredients and methods of treating allergic diseases based on the use of the said compositions.